Photoshop Elements Trick

See the lighted bubbly stuff in the fish bowl? Totally Fake.
If you take a gander at the 'Textures' on SkeletalMess' Flickr Stream, you'll see this one:

Perfect. Since I have a fishy in need of 'bellished bubbles.

After I boosted the levels and color a bit in my original shot, I simply created a new layer, adding in this bad boy 'texture' over the top. Then enlarged it to size it right and move it over the bowl.

Next I tested a couple blending styles.
First: Soft Light, but it blended in too much, went away. I wanted to still SEE the bubbles!
Second: Hard Light.. ahhh perfect..

I brought down the Opacity to 75%. Blending it even more, making it just subtle enough you aren't sure if they are real or not...

Last I used a soft eraser brush dialed down to 20% Opacity (elements has no 'flow' to adjust.. bummer) to erase everywhere the 'bubbles' layer was showing outside of the fishbowl or where they were covering the fish and greenery.

Voilá.

I give you Mood Lighting for our new fish: ANDY.
Quite possibly the BEST white elephant gift ever.

Giving Credit:
SkeletalMess allows use of textures for free, when you acknowledge his greatness.

All names have been changed to protect the innocent. AKA the fish.